Vat dyestuff.



- c. g. halogen, sulfur,

. naphthol, especially 4- -"bronaml-naphthol, 4c-chloro-l-naphthol. 20crystalline powders in 1500 parts'of dry chlorobenzene; stirring ,iscontinued for 12 hours.

- and Rumour Manna, residingat Elberfeld', Germany, citizens of byeasily 'movable or replaceable substitue'nts,

added to a warm solution,

blue color, scarcely soluble in' hot benzene 00., 0E EilLBERFEI-D,GERMANY,

UNITED sutures PATENT OFFICE.

WILHELM BAUER, OF VOHWINKEL, AND ALFRED HEBBE AND RUDOLF MAYER, 0FELBEBF'ELD,. GERMANY, ASSIGNOBS T0 FAB'BENFABRIKEN VORM. FRIEDR. BAYER &A. GORPOEATIQN OF'GERMANY.

VAT -DYE$TUFF.

Kc Drawing". Application filed To all it may comm: 1

.Be it known that we, Wmnumu BAUER, residing at Vohwmkel, and ALFREDHenna the German Empire, have invented new and in New Vat 'Dyestuil, ofwhich the follow: ing is a specification.

ZOur invention relates to the manufacture and production of new andvaluable vat dyestufis'. They are obtained by. condensing heta-naphthisatin derivatives containing more than one halogen atom inwhich the isreplaced oxygen of'tbe alpha-keto group I the amino group, the alkoxygroup with a para-substituted alpha-- thoxy-l-naphthol, 4:"

The new dyes are in a dry state dark blue with a metallic. luster whichare soluble in hot nitrobenzene generally with a. blue coloration, andwhich yield with hydrosulfite and caustic soda lye genorally yellowvatsdyeing cot-ton after ex posture to air blue-gray to black. shades re--markeble for their fast-noes to chlorin. In order to illustrate the newprocess more fully we can proceed as follows, the parts being by weight:-355 parts of dibromobeta naphthisatin are converted into thealpha-chlorid by heating them with 220 parts of P01 and 3500 parts ofdry chlorobenzene. The mixture thus obtained is then which is wellstirred, of 250 parts of e-bromo-l-naiphthol After cooling the dye isfiltered off and washed with benzene and ether.

centrated sulfuric acid with a greenish dark with a blue color, solublein hot nitrob'en- Stecifloation of Letters Patent.

time 18, 1910. Serial No. 567,689..

useful Improvements 1 1 alpha. chlorid and crystalline powder soluble inconcentrated sulfuric acid with a scribing witnesses.

It is a dark blue crystalline powder with a copper luster soluble incon- Patented Mar. 7, 1911.

zone with a greenish-blue color. It forms a yellow vatwi-th hydrosulfiteand caustic alkali, from which cotton is dyed after exposure to air infast grayish-blue to black shades.

Dichloro-beta-naphthisatin and higher halogenated beta-naphthisatinsfurnish similat products.

1. The herein described newdyestutls obtainable fIOll'l a halogenatedbeta-naphthisatin derivative.containing more-than one halogen atom inwhich the oxygen oi the alpha-keto group is replaced by easily movableor replaceable substituents and a parasubstituted alpha-naphthol. whichdyestuils are in a dry state dark blue crystalline powders with ametallic luster which are soluble in hot nitrobenzene generally with ablue coloration, and which yield withhydrosultite and caustic soda lyevats dyeing cotton after exposure to air from grayish-blue to blackshades remarkable for their fastness to chlorin, substantially asdescribed.

2. The herein described new dyestutl obtainahle fromdibroino-beta-naphthisatim 4.- bromo 1 naphth'ol, which dyestu'fl is in.a dry state a dark blue with a copper luster,

dark greenish blue color, and which yields with hydrosulfite and causticlye ayellow vat from which cotton is dyed a gray ish-blue to blackremarkable for its fastness to chlorin, substantially as described.

In testimony whereof we have hereunto set our hands in the presence oftwo sub- WI-LHELM BAUER. lL. 5.1 ALFRED HERRE. [was] RUDOLF MAYER.'[L.S.]

Witnesses:

Orro Konie, CHAS. J. lvmon'r.

